package com.gogowan.agroenterprise.supply.utils;


class MyHash {
    /**//**
     * 加法hash
     * @param key 字符�?
     * @param prime �?��质数
     * @return hash结果
     */
     public static int additiveHash(String key, int prime)
     {
         int hash, i;
         for (hash = key.length(), i = 0; i < key.length(); i++)
             hash += key.charAt(i);
         return (hash % prime);
     }
     
     /**//**
     * 旋转hash
     * @param key 输入字符�?
     * @param prime 质数
     * @return hash�?
     */
     public static int rotatingHash(String key, int prime)
     {
         int hash, i;
         for (hash=key.length(), i=0; i<key.length(); ++i)
             hash = (hash<<4)^(hash>>28)^key.charAt(i);
         return (hash % prime);
         //   return (hash ^ (hash>>10) ^ (hash>>20));
     }
     
     // 替代�?
     // 使用：hash = (hash ^ (hash>>10) ^ (hash>>20)) & mask;
     // 替代：hash %= prime;

     /**//**
     * MASK值，随便找一个�?，最好是质数
     */
     static int M_MASK = 0x8765fed1;
     /**//**
     * �?���?��hash
     * @param key 输入字符�?
     * @return 输出hash�?
     */
     public static int oneByOneHash(String key)
     {
         int   hash, i;
         for (hash=0, i=0; i<key.length(); ++i)
         {
             hash += key.charAt(i);
             hash += (hash << 10);
             hash ^= (hash >> 6);
         }
         hash += (hash << 3);
         hash ^= (hash >> 11);
         hash += (hash << 15);
         //   return (hash & M_MASK);
         return hash;
     }
     
     /**//**
     * Bernstein's hash
     * @param key 输入字节数组
     * @param level 初始hash常量
     * @return 结果hash
     */
     public static int bernstein(String key)
     {
         int hash = 0;
         int i;
         for (i=0; i<key.length(); ++i) hash = 33*hash + key.charAt(i);
         return hash;
     }
     
     //
     /**///// Pearson's Hash
     // char pearson(char[]key, ub4 len, char tab[256])
     // {
     //   char hash;
     //   ub4 i;
     //   for (hash=len, i=0; i<len; ++i)
     //     hash=tab[hash^key[i]];
     //   return (hash);
     // }
     
     /**///// CRC Hashing，计算crc,具体代码见其�?
     // ub4 crc(char *key, ub4 len, ub4 mask, ub4 tab[256])
     // {
     //   ub4 hash, i;
     //   for (hash=len, i=0; i<len; ++i)
     //     hash = (hash >> 8) ^ tab[(hash & 0xff) ^ key[i]];
     //   return (hash & mask);
     // }
     
     /**//**
     * Universal Hashing
     */
     public static int universal(char[]key, int mask, int[] tab)
     {
         int hash = key.length, i, len = key.length;
         for (i=0; i<(len<<3); i+=8)
         {
             char k = key[i>>3];
             if ((k&0x01) == 0) hash ^= tab[i+0];
             if ((k&0x02) == 0) hash ^= tab[i+1];
             if ((k&0x04) == 0) hash ^= tab[i+2];
             if ((k&0x08) == 0) hash ^= tab[i+3];
             if ((k&0x10) == 0) hash ^= tab[i+4];
             if ((k&0x20) == 0) hash ^= tab[i+5];
             if ((k&0x40) == 0) hash ^= tab[i+6];
             if ((k&0x80) == 0) hash ^= tab[i+7];
         }
         return (hash & mask);
     }
     
     /**//**
     * Zobrist Hashing
     */
     public static int zobrist( char[] key,int mask, int[][] tab)
     {
         int hash, i;
         for (hash=key.length, i=0; i<key.length; ++i)
             hash ^= tab[i][key[i]];
         return (hash & mask);
     }
     
     // LOOKUP3
     // 见Bob Jenkins(3).c文件
     
     // 32位FNV算法
     static int M_SHIFT = 0;
     /**//**
     * 32位的FNV算法
     * @param data 数组
     * @return int�?
     */
     public static int FNVHash(byte[] data)
     {
         int hash = (int)2166136261L;
         for(byte b : data)
             hash = (hash * 16777619) ^ b;
         if (M_SHIFT == 0)
             return hash;
         return (hash ^ (hash >> M_SHIFT)) & M_MASK;
     }
     /**//**
     * 改进�?2位FNV算法1
     * @param data 数组
     * @return int�?
     */
     public static int FNVHash1(byte[] data)
     {
         final int p = 16777619;
         int hash = (int)2166136261L;
         for(byte b:data)
             hash = (hash ^ b) * p;
         hash += hash << 13;
         hash ^= hash >> 7;
         hash += hash << 3;
         hash ^= hash >> 17;
         hash += hash << 5;
         return hash;
     }
     /**//**
     * 改进�?2位FNV算法1
     * @param data 字符�?
     * @return int�?
     */
     public static int FNVHash1(String data)
     {
         final int p = 16777619;
         int hash = (int)2166136261L;
         for(int i=0;i<data.length();i++)
             hash = (hash ^ data.charAt(i)) * p;
         hash += hash << 13;
         hash ^= hash >> 7;
         hash += hash << 3;
         hash ^= hash >> 17;
         hash += hash << 5;
         return hash;
     }
     
     /**//**
     * Thomas Wang的算法，整数hash
     */
     public static int intHash(int key)
     {
         key += ~(key << 15);
         key ^= (key >>> 10);
         key += (key << 3);
         key ^= (key >>> 6);
         key += ~(key << 11);
         key ^= (key >>> 16);
         return key;
     }
     /**//**
     * RS算法hash
     * @param str 字符�?
     */
     public static int RSHash(String str)
     {
         int b    = 378551;
         int a    = 63689;
         int hash = 0;
         
         for(int i = 0; i < str.length(); i++)
         {
             hash = hash * a + str.charAt(i);
             a    = a * b;
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of RS Hash Function */
     
     /**//**
     * JS算法
     */
     public static int JSHash(String str)
     {
         int hash = 1315423911;
         
         for(int i = 0; i < str.length(); i++)
         {
             hash ^= ((hash << 5) + str.charAt(i) + (hash >> 2));
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of JS Hash Function */
     
     /**//**
     * PJW算法
     */
     public static int PJWHash(String str)
     {
         int BitsInUnsignedInt = 32;
         int ThreeQuarters     = (BitsInUnsignedInt * 3) / 4;
         int OneEighth         = BitsInUnsignedInt / 8;
         int HighBits          = 0xFFFFFFFF << (BitsInUnsignedInt - OneEighth);
         int hash              = 0;
         int test              = 0;
         
         for(int i = 0; i < str.length();i++)
         {
             hash = (hash << OneEighth) + str.charAt(i);
             
             if((test = hash & HighBits) != 0)
             {
                 hash = (( hash ^ (test >> ThreeQuarters)) & (~HighBits));
             }
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of P. J. Weinberger Hash Function */
     
     /**//**
     * ELF算法
     */
     public static int ELFHash(String str)
     {
         int hash = 0;
         int x    = 0;
         
         for(int i = 0; i < str.length(); i++)
         {
             hash = (hash << 4) + str.charAt(i);
             if((x = (int)(hash & 0xF0000000L)) != 0)
             {
                 hash ^= (x >> 24);
                 hash &= ~x;
             }
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of ELF Hash Function */
     
     /**//**
     * BKDR算法
     */
     public static int BKDRHash(String str)
     {
         int seed = 131; // 31 131 1313 13131 131313 etc..
         int hash = 0;
         
         for(int i = 0; i < str.length(); i++)
         {
             hash = (hash * seed) + str.charAt(i);
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of BKDR Hash Function */
     
     /**//**
     * SDBM算法
     */
     public static int SDBMHash(String str)
     {
         int hash = 0;
         
         for(int i = 0; i < str.length(); i++)
         {
             hash = str.charAt(i) + (hash << 6) + (hash << 16) - hash;
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of SDBM Hash Function */
     
     /**//**
     * DJB算法
     */
     public static int DJBHash(String str)
     {
         int hash = 5381;
         
         for(int i = 0; i < str.length(); i++)
         {
             hash = ((hash << 5) + hash) + str.charAt(i);
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of DJB Hash Function */
     
     /**//**
     * DEK算法
     */
     public static int DEKHash(String str)
     {
         int hash = str.length();
         
         for(int i = 0; i < str.length(); i++)
         {
             hash = ((hash << 5) ^ (hash >> 27)) ^ str.charAt(i);
         }
         
         return (hash & 0x7FFFFFFF);
     }
     /**//* End Of DEK Hash Function */
     
     /**//**
     * AP算法
     */
     public static int APHash(String str)
     {
         int hash = 0;
         
         for(int i = 0; i < str.length(); i++)
         {
             hash ^= ((i & 1) == 0) ? ( (hash << 7) ^ str.charAt(i) ^ (hash >> 3)) :
         (~((hash << 11) ^ str.charAt(i) ^ (hash >> 5)));
         }
         
         //       return (hash & 0x7FFFFFFF);
         return hash;
     }
     /**//* End Of AP Hash Function */
     
     /**//**
     * JAVA自己带的算法
     */
     public static int java(String str)
     {
         int h = 0;
         int off = 0;
         int len = str.length();
         for (int i = 0; i < len; i++)
         {
             h = 31 * h + str.charAt(off++);
         }
         return h;
     }
     
     /**//**
     * 混合hash算法，输�?4位的�?
     */
     public static long mixHash(String str)
     {
         long hash = str.hashCode();
         hash <<= 32;
         hash |= FNVHash1(str);
         return hash;
     }
     /**//**
      * 混合hash算法，输�?6进位的hash�?
      */
      public static  String mixHashStr(String str)
      {
          return Long.toHexString(mixHash(str));
      }
}
